Method of producing one-piece drawn containers



fia arii M, 1931. J. M. HOTHERSALL METHOD OF PRODUCING ONE-PIECE DRAWN CONTAINERS Filed. Feb. 13, 1929 4 Sheets-Sheet l dMlf/WENTQR Mum ATTORNEY 1931- J. M. HOTHERSALL 1,800,531

METHOD OF PRODUCING ONEPIECE DRAWN CONTAINERS Filed Feb. 13 1929 4 SheetsSheet 2 INVENTOR ATTORNEY April 14, 1931. J. M. HOTHERSALL 3 METHOD OF PRODUCING ONE-PIECE DRAWN CONTAINERS Filed Feb. 13 1929 4 Sheets-Sheet 3 ATTORNEY W 1931. J. M. HOTHERSALL 1,800,531

METHOD OF PRODUCING ONE-PIECE DRAWN CONTAINERS Filed F' eb. l3 1929 4 Sheets-Sheet 4 INVENTOR ATTORNEY Patented Apr. 14, 1931 UNITED. STATES PATENT orrlcs JOHN M. HOTHEFSALL, OFBBOOKLYN, NEW YORK,' ASSIGNOR T0 AMERICAN COI- PANY, OF NEW YORK, N. Y CORPORATION OF NEW JERSEY METHOD OF PRODUCIN ONE-PIECE DRAWN CONTAINERS 'Applicationjled rebmar 1s, 192a. Serial No. 839,560.

This invention relates to an improved method of producing a one-piece drawn sheet metal container provided with a flanged portion adapted for connection with a container cover.

In the manufacture of containers having drawn side walls, it has been customary to trim the edge after the drawing operation as a certain amount of edge irregularity results from the uneven strains: introduced throughout the metal by the drawing action. Such containers prior to the present invention are first blanked, then formed (usually in the same machine) either directly from a sheet of material or from strips first sheared from the sheet. The latter practice is adapted to automatic production of such BOIltfilll; ers. In either method as a factor of safety the blanking line has been spaced at least an eighth of an inch from the sheet or strip edge to insure sufficient material remaining in the skeleton of the sheet or strip to permit of its being handled. This skeleton material constitutes a great waste. The blank must be sufficiently large to provide a drawn container and according to present methods to provide extra material as a factor of safety for a trim. This constitutes a second waste. a

The present invention dispenses entirely with the blanking operation, the container being drawn directly from a scroll-shaped subdivisionor section of the sheet without the usual remaining skeleton. There being no skeleton, the first waste mentioned is avoided That part of the sheet, the section, from which the container is drawn according to the present invention does not follow the outlineof the container as is usual where the container is'first blanked and then drawn from the blank. Therefore, the usual allowance for a trim need not be made. That is to say, the trimming line, in the present invention, may coincide with the edge of the sheet part only at its narrowest place and the usual eighth of an inch allowance onboth sides of the blank edge is thus saved.

The principal object of the present invention, therefore, is the provision of a process for the manufacture of a flanged, one-piece drawn container using a. minimum number of operations with a minimum waste of the material from which the container is made.

A further important object of the invention is the provision of a process for the manufacture of a flanged, one-piece, drawn container wherein the sheet from which the.-

container is formed is first out into a series of strips of a shape suitable for economic handling by automatic means and wherein divisions of the strip are used to form the container. V

Numerous other objects and advantages of the invention will be a parent as it is better understood from the ollowing description, which, taken in connection with the accompanying drawings, discloses a preferred embodiment thereof. Referring to the drawings:

- Figure 1 is a diagrammatic view of a sheet showing infull lines the outline of the scroll strips to be cut therefrom and indicating the extent of the sections of the strip by means of the dotted lines;

Fig. 2 is a perspective view of a drawn tional view, taken substantially along line 7-7 of Fig. 6, and

Fig. 8 is a transverse, sectional fragmentary view of a conventional trimming mechanism.

A sheet 21 (Fig. 1) is first fed to a shearing mechanism which shears the same along lines of severance 22. For purposes of illustration, a drawn container of oval shape is.

selected and ,in the sheet lay-out for this shape of container, the lines of severance 22 are of scroll or undulating form, this giving scroll-shaped strips and a greater efiiciency in cutting. The shearing operation divides the sheet into strips, th e re being disclosed a.

and drawing mechanism which first succes sively cuts offsections-ofthe strip along the straight lines 23, thereby producing sections C. Following the cutting of eachsection C from the strip it is drawn intov the forum of the shell body 1)? illustrated in 'Fig.; 2.

This produces a ,drawn shell 24 and "an undrawn flange 25. r This shell body D is then fed to a trimming mechanism which removes theexcesspart of the flange 25-, therebyform-' ing the completed one-piece drawn container E provided with -flange 2 6, as illustrated in:

Fi l3. V

it will be observed (Fig. 1 that the two strips Biare'narrower than the central strip A, the upper line of severance 22 of upper strip B and the lower'line'of severance of lower stripB{being incomplete; The entire width of stripiA: is not required to form the container the shell body (Fig. 2) when formed from a strip B having a part of tne edgeof itsflange 25 cut away, as indicated by the dotted line 27;This, however, is inside of orcoincident at -one OlIltiWltll'tllQ trimmingline and .tbecomp' etc container E- is always the same whether formed'fro'm' 2158131311) A or. from, a strip" B. This graphically illustrates how, int-he present invention, it is possible to dispense withthe us alfaictor of safetyas allowancefor atrim; A relatively narrower sheet 21, which need not. be trimmed, is thus used and a saving of'thematerial resultsi r i Notching dies in the she'aringimechanism operate on sheet '21.(Fig. 1) to provide the resulting strips A and B with gauge reference notches. 'A-' gauged notch .on each strip is used in connection with a complete scroll side edge thereof to insure proper feeding of the strip through the cutting and drawing mechanism, as will be hereinafter fullyset forth. r 1 1 Strip A 's accordingly provided with a notch 28 while the strips B receive notches 29 and 31. Only'one of the notches of strip B is used as a reference element, but two notchesare cut by the notching dies in order to correctly position a notch relative to the complete scroll edge thereof, regardless-of whether it is the upper or the lower strip 1 .B. This will become more apparent as the frame 32 and forms the surface over which sheet 21 is moved through the machine.

formed with notching diesand 39which cooperate with corresponding die-elements carried" by the die 37. Die 35 also carries a notching die 41 which cooperates with a notching punch 42 carried by the slide 36.

As the sheet 21 is out along the lines of severance 22, a strip- A orfB is pushed through the opening in "the-die member 35 and in,a'correspondingopening formed in the bolster'plate' 33 and falls onto a discharge chute 43. Part of the sheet which is positioned forward of the die 35 falls over an inclined surf-ace 44 of the said die and certain rear parts of the sheet fall through an-opening 45 and onto a discharge chute 46. The usual-Qform of knock-out for the forward strip or forward-part of the sheet comprises a knock-out pin 47 slidably held in: a bracket 48 projected. "fromthe forward face of the slide 36,*-'and a spring 491tends to hold the pin 47 in'lowered position; Sheet 21 "is, fed

over the feed tablet34 and, through the die mechanism just described by feed bars 51 of usual'construction sliding in guideways' 52 7 formed in the table 34 and carryingspringpressed dogs 53. .A guide bar 54-is held spaced above the surfac'e-ofthe table '34 and forms retainingmeans forsheet 21*as'it is fedthrough the machine; Spring pressed or gravity operated dogs 55 pivoted to-bar 54 prevent'backward travel of sheet 21 with the return travel of feed bars 51.- I

" In thelay-out disclosed in Fig. 1, sheet 21 is first positioned between the fixed and movable die mechanism so thatthe spaced scroll cut edgesof the die partssever the upper strip-B and move it downwardly through the lower die. and onto the discharge chute 43. The irregular shaped pieces of the upper part of sheet-21 above the upper line of severance 22 during this cutting action fall .over the, inclined surface 44. During this cutting action, notches 29 and'31 are cut by the notching die parts, 38 and 39 and the notch 28 is cut in the central strip A by the die parts 41 and 42.

The second position of sheet 21 severe the central rip A -and-the lower .strip B therefor.

prises a standard form of press (illustrated in Figs. 5, 6, and 7). This mechanism comprises a supporting frame indicated at 56 having a supporting bed 57 formed integral therewith. A feed table 58 is mounted u on the bed 57 and forms the supporting sur ace over which the strips A or B are fed into the cutting and drawing mechanism. The cutting and drawing elements comprise a drawing die 59 carried by the bed 57 and secured thereto by bolts 61. The drawing die 59 also carries cut edges 62 secured to opposite walls of the die. These constitute the stationary die-elements.

The movable die elements comprise a slide 63 mounted in a usual or preferred manner and having up and down movement. The slide 63 carries apunch block 64 which is secured to the bottom end thereof by bolts 65. Cut edges 66 are screwed into the opposite sides of the punch block 64 and co-act with the cut edges 62 when the punch block is in lowered position. 1 The drawing punch 67 is mounted within slide 63 and extends through the punch block 64 and has movement relative to the slide and block. The drawing punch 67 cooperates with the drawing die 59 for forming the drawn shell body of'the container in a manner hereinafter described. A knock-out pad 68 is positioned within the opening formed in the drawing die 59 and is raised and lowered in proper time relation with the other operating parts of the press mechanism.

A knock-out rod 69 is secured to the pad 68 and forms the actuating connection Both slide and block and the drawing punch elements are actuated in proper time relation to effect the cutting of strips A of B as they are fed over the table 58 by a standard form of feed mecha- IllSIIl.

As illustrated in Figs. 6 and 7, a strip A rests on the feed table 58 and is moved toward the cutting and drawing mechanism just described by a feed bar 71 sliding in a guide-way formed in table 58 and carrying the usual standard type of pivoted springpressedfeed dogs 72. The press mechanism is inclined at an angle in the usual manner, as indicated in Fig. 5, and the strip A resting on table 58 is held by gravity against a rear guide 73 formed in table 58. In this position of strip A, the scroll edge adjacent slot 28 is against the guide 73. Where the upper strip B instead of strip A is used in the press, its full scroll edge is positioned against the guide 73, this bringing its notch 31 intopropei feed'ing position. Where the lower strip B is in the press,

its full scroll edge is positioned against the guide 73 and its notch 29 is in proper position. The feed bar 71 is moved back and forth to move the strip through the machine, a feed dog 7 2 engaging within a notch 28, 29 or 31 depending upon the kind of strip.

A locating device is used at the cutting and drawing station for properly centering the strip prior to the cutting of a section C therefrom. This centering mechanism comprises centering blocks 74 and 75 mounted on rods 76 oscillating within suitable openings formed in the drawing die 59 and in bed 57. Fig. 6 illustrates in dotted lines the position of the centering blocks as strip A or B is brought into cutting position. As the, strip is broughtto rest at theend of the forward stroke of feed bar 71, rods 76 are oscillated in any suitable manner to position blocks 74 and 75, as illustrated by the full line position in Fig. 6. It will thus be read ily seen that in this position the blocks 74 and 75 engage the scroll edges of the strip and center the end section 0 for cutting and drawing. The slide 63 is thereupon lowered and cut edges 66 cooperate with their associated cut edges 62 and cutting along lines 23 of section C sever it from the remaining part of the strip.

In the event of a strip A being operated upon, the first cutting action severs an end piece F forward of the dies and removes the first section C from the end of the strip. This is illustrated in Fig. 6. In the,

event that strip B is being operated upon,

the first cutting action merely removes a small trim from the forward end of the strip.

Immediately following the cutting action, the punch block 64 continues its downward movement and engages section C in a slip grip between the lower face of the block 64 and the upper surface of the drawing die 59. The drawing punch 67 then further descends and forces a part of section G into the opening within the drawing die 59 to produce the drawn shell 24 of the shell body D. Following the drawing action, punch 63 and associated parts are raised, the shell" body D at such time remaining in the low? erdrawing die 59. Knock-out pad 68 is then raised and the shell body D is lifted from position within the drawing die 59 to a position wherein its lower surface is in alignment with a discharge chute 77 formed between the guides 78 formed on thefeed table 58. To permit discharge of the shell body D from the die mechanism, the centering blocks 74 and 75 are moved to dotted position, as illustrated in Fig. 6 whereupon the shell body D moves by gravity into the chute 77.

A chute 79 lies forward of and adjacent to chute 77 and has a side wall 78 in common with one wall of chute 77, and a wall 81 formed in the feed table 58. The end piece .F falls by gravity into chute 79 as soon as it is severed from the strip A, and is thereby discharged out of the machine.

This cutting and drawing operation is repeated on strip A until at the final cutting action, the rear end piece G is cut from the section 0 ad o1n1ng. The severed end piece G thereupon falls into a chute'82 in,-

therear of and adjacent to chute 77. Chute 82 has one side wall 78 in common with one ar the walls 6f chute 77 and has a side wall 83 formed in the feed table. To permit dis- 9 char e movement of end piece G by gravity within the chute 82, a gate 84 pivotally carried on'the upper end of a rock shaft 85 oscillating in a bearing formed in table 58 is moved to the dotted position illustrated in Fig. 6. The gate'84 normally constitutes a continuationof the guide rail 7 3-when in the osition illustrated in full linesin Fig. 6. in the event that a strip B is beingoperated upon, there is no end piece severed therefrom and the final cutting action removes remaining part of, the strip.

D is then fed into a trim- 1 the last section G without there being any The shell body 'ming mechanism, the principal parts of .which are illustrated in Fig. 8. This may be any suitable form of trimming press comprising, for example, a supporting frame 86 and a supporting bed 87 formed integrally there-.vith This is also inclined in the usual manner as illustrated in the drawing. A

die block 88 is secured by bolts 89 to the-bed 87 and constitutes the fixed part of the trimming mechanism. A slide 91, mounted in any suitable and usual manner for vertical movement, carries at its lower end a trimming punch 92 to which is secured a centering pad 93. .The trimming punch 92 and centering pad 9? operate through anopening in a stripper ring 94' carriedby bracket 95 mounted on the lower die 88.

The shellbody D? is positioned within the die 88 by a suitable and usual form of mechanism with its flange 25 resting on the upper surface of the die and the drawn shell part 24 resting within the opening of the die 88. Upon lowering of the slide 91, the centering pad 93 enters-within the shell body 24 and the lower cut edge of the trimming punch .92 cooperates with the side walls adJacent the opening in the die 88 to cut from flange the under'tace of the stripper ring 94 is stripped oil of the trimming punch 92 and falls'by gravity onto the inclined plate 98 andslides-out of the machine.

It is thought that the invention anl' 'many of its attendant advantages will be understood. from the foregoing description, and

it willlbe apparent that various changes may be made in the form, construction andare rangement of the parts without departing from the spirit and scope of the invention or sacrificing all of its material advantages, the form hereinbefore described being merely a preferred embodiment thereof.

I claim! r V :1. The. process. of producing ,cne-piece drawn containers which comprises shearing a sheet of material at intervals along lines of severance producing, a series of scrollshaped strips, cutting the strips at intervalsalong other lines of severance'producing a series of sections, drawing each section along predetermined lines producing a body hav ing a drawn shell andan undrawn flange, and {rimming the flange along predetermined mes. f V

r 2. The process of producing one-piece drawn containers which comprises first preery which comprises presenting a sheet of material to a shearing mechanism and obtaining thereby scroll-shaped strips suitable for automatic feeding in an automatic strip press feed mechanism, feeding the strip automatically by such a feed mechanism to a cutting and forming press and obtainin therefrom a drawn, flanged shell body, an presenting said body to a trimming operation and obtaining therefrom the completed one-piece drawn container.

' 4. The process of producing non-rectan-r gular, one-piece, drawn containers which comprises shearing-a sheet of material along spaced, undulating-lines of severance producing a series of scroll-shaped strips, cutting the strips along spaced straight lines of severance producing. a series of sections, drawinga section into a shell part and. an extended flange, and trimming the flange along a line parallel to the drawn Wall of the tamer.

shell part and producing the complete con- 

